Chemistry and Materials Science

Abstract: Point to the manufacturing process of variable-section rectangular tube, a four-die radial extrusion process was designed in this article. The general deformation law was researched in two-dimensions, the influence of deformation parameters on the deformation results was explored, and the method by using the mold anti-deformation to eliminate the concave defects was proposed. For the tube parts with common thickness to diameter ratio, the corresponding optimal die arc degree is obtained through simulation and optimization. After that, the two-dimensional deformation law is applied to three dimensions, and the methods to eliminate the defect are carefully studied and successfully realized. Taking a variable-section rectangular tube as an example, the experiment was carried out. The experimental results were compared with the simulation results, and the accuracy of the simulation results and the feasibility of the process were verified.

Abstract: Dephosphorisation in oxygen steelmaking depends on more than the equilibrium phosphorus partition ratio. It also depends on where gas, slag, metal and injected lime powder coexist while the bath is being stirred. We develop a gas–slag–metal–particle reaction model for bottom-blown oxygen–CaO powder injection by coupling Euler–Euler transport of liquid steel, mixed slag and gas with discrete CaO-particle motion. The local source terms include oxygen dissolution, FeO/Fe₂O₃ conversion, CO/CO₂ buffering, competitive C/Si/P oxidation, P₂O₅ formation, C₂S–C₃P fixation, reaction heat and phase-wise mass conservation. Instead of resolving every bubble or slag droplet, the model represents bubble swarms, dispersed slag and emulsified metal–slag contact through mean-field interfacial area densities tied to local phase fractions and mixing. Two cases with the same initial phosphorus content but different carbon levels are used to test reaction selectivity. In the high-carbon bath, bottom-blown oxygen is consumed first by decarburisation; the generated CO sustains plume buoyancy but reduces FeO_x retention during flotation. CaO addition improves local slag formation, but it contributes to dephosphorisation only where FeO_x supply, P₂O₅ generation and C₂S–C₃P fixation coincide at an active slag–metal interface. The stable dephosphorisation window therefore lies mainly in the upper slag–metal mixing zone, not in the bottom gas column. The model provides a computable basis for analysing bottom powder injection, combined blowing and low-carbon endpoint dephosphorisation in gas–slag–metal reactive flows.

Abstract: Cu-based interpenetrating phase composites (IPCs) represent a paradigm for sliding electrical contacts where the synergy between thermal management, wear resistance, and electrical transport is critical. Herein, we engineer Cu-(CrWₓ)C IPCs (x = 0, 10, 25, 50 wt%) via pressureless infiltration, elucidating a tungsten-mediated architectural stabilization mechanism. We demonstrate that controlled W incorporation refines the carbide skeleton, optimizing the load-transfer efficiency between the rigid ceramic network and the continuous Cu-rich functional phase. Microstructural characterization (XRD, SEM/EDS) confirms the intact three-dimensional interpenetration, with higher W content promoting the segregation of W-rich domains. Quasi-static compression (10-3 s-1) validates the structural robustness under large-strain regimes. Notably, all composites retain high electrical conductivities (~39–41 % IACS); the Cu-(CrW10)C variant exhibits the peak thermal conductivity at 500 °C. Tribological evaluations reveal that optimal wear resistance is decoupled from peak hardness; instead, it arises from the stabilization of a skeleton-supported tribo-damaged layer facilitated by moderate W addition. Conversely, excessive W enrichment induces brittle fragmentation and interfacial debonding, exacerbating third-body abrasion. Quantitative analysis using a Thermo-Tribological Performance Index (TTPI) and an Electrical-Thermal-Wear Balance Index (ETWBI) confirms that Cu-(CrW10)C achieves the optimal equilibrium among material removal resistance, heat dissipation, and dimensional stability. This work establishes a design strategy for high-performance IPCs by leveraging architectural tuning to reconcile traditionally conflicting property requirements.

Abstract: Sintering diagram for copper fibers is established based on a two joint-fiber geometric model and intrinsic material constants, with comprehensive consideration of four neck-growth mechanisms: volume diffusion, grain-boundary diffusion, surface diffusion and Nabarro-Herring microcreep. The sintering diagram reveals that grain-boundary diffusion dominates neck growth at relatively low temperatures, surface diffusion prevails at high temperatures for short holding time, and Nabarro-Herring microcreep acts as the primary mechanism at high temperatures for long holding time, respectively. In addition, synchrotron radiation X-ray computed tomography (SR-CT) characterization is adopted to validate the established sintering diagram via the measured neck size of sintered fiber joints. The experimental results show that most measured neck-size data points lie close to the theoretical curve predicted by the Nabarro-Herring microcreep mechanism when sintered at 1030 oC for 30 min, 60 min and 180 min. This result confirms that Nabarro-Herring microcreep is the predominant neck-growth mechanism at high temperatures for long holding time, which is consistent with the theoretical result derived from the sintering diagram. Meanwhile, the results also prove the existence of Nabarro-Herring microcreep during the high-temperature sintering of copper fibers without externally applied pressure.

Abstract: This article analyzes in detail the structural, thermal and mechanical properties of the Ni₅₄Cr₂₈Mo₈Nb₅Ta₅ alloy, as well identify potential applications in areas where exceptional high-temperature performance is required — such as gas turbines, nuclear reactors or aeronautical engine components. Obtaining a very good correlation between the experimental and fitted profiles, as well as the low values of the error parameters (R-factors), confirms the accuracy of the structural model and the validity of the phases identified following the XRD analysis. The study also aims to highlight the relationship between chemical composition, microstructure and mechanical behavior, providing a basis for optimizing heat treatments and manufacturing processes of this advanced superalloy.

Abstract: Platinum-Rhodium alloys are one of the prominent alloys used in the high temperature and high corrosion environment. Due to the nature of Pt and Rh, it maintains the single solid solution phase up to very high temperature. In order to develop and design a new part to be used in the field, many techniques, tools, software in combination are needed. Phase field method (PF) is used for microstructure prediction or finite element method (FEM) for stress analysis. Those methods require additional data such as thermodynamic stability for PF and elastic modulus for FEM. Pt-Rh binary system, the experimental data for thermodynamic stability and elastic properties are very limited and mostly available only for pure elements. In this work, we performed first-principles calculations to predict the temperature dependent elastic properties of fcc-disordered PtRh alloys at various concentrations. The special quasirandom structures (SQS) are used to describe the disordered structure of fcc-disordered PtRh alloys. Vibrational contribution to the free energy are performed with the quasi-harmonic phonon approximation to obtain the finite-temperature free energy and coefficient of thermal expansion for the fcc-disordered PtRh alloys. The elastic stiffness of the fcc-disordered PtRh alloys at different concentrations are obtained through the energy-strain method. By coupling between calculated coefficient of thermal expansion and the elastic stiffness data calculated at various volumes, the finite-temperature elastic stiffness of the fcc-disordered PtRh alloys can be obtained.

Abstract: Commercial aluminum (Al) metals contain unavoidably iron (Fe) and silicon (Si) as impurities. Due to its low solubility and high chemical affinity to Al, Fe exists in the form of Fe-containing intermetallic compounds (Fe-IMCs) which act crucially in solidification processes, determining the micro-structure and consequently the mechanical performance of the cast parts. Meanwhile, Si as impurity or addition may join the binary Fe-IMCs. Here, we investigate the Si stabilization effects on the frequently observed Al-rich Fe-IMCs in a comprehensive and systematical way using a first-principles density-functional theory (DFT) approach. The study revealed different Si stabilization effects on the cubic α- and hexagonal αʹ-phase, as well as other binaries: Al₁₂Fe, η-Al₆Fe, τ₄-, β- and θ-phases. The enhancement of stability for the α-phase is moderate while it is strong for the αʹ-phase. For the stability series (from higher to lower) is θ-Al₁₃Fe4 > η-Al₆Fe >α-Al_4.75Fe in the binary system, while it becomes τ₄-(Al,Si)₅Fe>β-Al_4.5SiFe >αʹ-(Al,Si)_4.174Fe for the ternary Fe-IMCs. The information obtained here helps understand the formation of Fe-IMCs particles during casting of Al-Si alloys, and design of novel Al alloys of fine micro-structures and desired mechanical performances of the products from the primary Al and the scraps and wastes.

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In this paper, the supersaturated solid solution of Al-Cu3-Si-Mg alloy prepared by molten metal die forging (MMDF) was used as the research object. The formation and evolution of precipitates during aging treatment were investigated through experiments at different temperatures and times, and the precipitation mechanisms and sequences of various precipitates were analyzed. The main precipitated phases formed in the supersaturated solid solution of Al-Cu3-Si-Mg alloy after aging treatment are θ(Al₂Cu), θ'(Al_3.6Cu₂), γ'(Al_0.63Mg_0.37) and η'(Cu, Si). Based on XRD and TEM analysis under different aging treatment conditions, the precipitation sequence is determined as follows: SSS → GP₀ → GP₀+γ'→GP₀+(γ'+γ)+θ''+η'→(γ'+γ)+(θ''+θ')+(η'+η)→(γ'+γ)+(θ+θ')+(η'+η)→(γ'+γ)+(θ+θ')+η→γ+θ+η. With increasing aging temperature and time, precipitates tend to accumulate at the α-Al grain boundaries. After aging treatment at 165-185 °C for 4 h, chain-like θ(Al₂Cu) precipitates are discontinuously distributed at the α-Al grain boundaries, disk‑shaped θ'(Al_3.6Cu₂) and θ''(Al₂Cu) phases mainly precipitate within the grains. When the temperature exceeds 185 °C, the chain-like θ(Al₂Cu) precipitates at the grain boundaries gradually become continuous, the amount of θ(Al₂Cu) phase in the grains increases significantly, θ''(Al₂Cu) disappears completely, and the size of θ'(Al_3.6Cu₂) decreases obviously. After aging treatment at 185 °C for 5-6 h, the chain-like θ(Al₂Cu) precipitates at the grain boundaries become more continuous, and their length fraction continues to increase with prolonged aging time.

Abstract: This study investigates the microstructural evolution and mechanical behavior of a Ni-based superalloy subjected to combined heat treatment and laser processing. Special emphasis is placed on the quantitative analysis of γ′ Ni₃(Al,Ti) and η (Ni₃Ti) phase distributions using SEM-based statistical methods. OM/XRD were employed for initial structural and phase identification, followed by detailed microstructural characterization using SEM/EDS. The results reveal that γ′ precipitates exhibit a fine and uniform distribution with a high number density, whereas the η (Ni₃Ti) phase appears as relatively coarse and sparsely distributed particles. Statistical size distribution analysis demonstrates that processing parameters significantly influence precipitate morphology and phase stability. Laser treatment promotes redistribution of γ′ precipitates and suppresses η (Ni₃Ti) phase formation, resulting in improved microstructural homogeneity. Mechanical characterization shows a strong correlation between γ′ Ni₃(Al,Ti) phase refinement and enhanced hardness and tensile properties. Fractography analysis indicates predominantly ductile fracture behavior with microvoid coalescence. The findings provide a quantitative understanding of phase evolution and establish a microstructure property relationship for optimizing Ni-based superalloys through advanced processing techniques.

Abstract: Since its introduction, focused ion beam (FIB) technology has expanded from micro/nanofabrication in the semiconductor industry into the field of multimodal characterization of metallic material microstructures. This article systematically reviews the latest research advances of FIB-SEM technology in the field of metallic materials science. The fundamental principles and system functions of FIB-SEM are introduced, with emphasis on its key applications in two-dimensional and three-dimensional morphological characterization, as well as specimen preparation for transmission electron microscopy (TEM) and atom probe tomography (APT). The combined strategies of FIB-SEM with electron backscatter diffraction (EBSD), time-of-flight secondary ion mass spectrometry (TOF-SIMS), and other characterization techniques are also discussed. Current developments indicate that FIB-SEM technology is advancing toward multi-ion-source synergy and multimodal integration. In the future, combined with artificial intelligence and big data analysis, it is expected to enable high-throughput, correlative measurements of multidimensional properties at the micro-scale, providing important technical support for "materials genome" research in metallic materials.

Abstract: Copper anodic slime is a valuable secondary resource for precious and critical elements such as gold, silver, selenium, and tellurium. In certain industrial flowsheets, copper anodic slime is smelted together with lead to facilitate silver and gold recovery, generating a fine lead‑rich fly ash as a secondary residue. This dust contains considerable amounts of selenium and tellurium and poses significant environmental and occupational health risks due to its high lead content and sub‑micron particle size. The present study investigates sodium carbonate (Na₂CO₃) leaching as an environmentally benign pre‑treatment approach aimed at partial removal of selenium and tellurium while simultaneously stabilizing lead through carbonate formation. Rather than targeting maximum metal recovery, the process is evaluated from a detoxification‑oriented perspective suitable for safer disposal or downstream recycling of hazardous metallurgical dusts. The effects of sodium carbonate concentration, temperature, solid‑to‑liquid ratio, and leaching time on selenium and tellurium recovery were investigated using a central composite design (CCD) implemented in Design‑Expert software. Under the investigated conditions, selenium recovery reached a maximum of 53.9%, while tellurium recovery remained generally below 15%, with a maximum observed value of approximately 33.9% in a specific experimental run. Scanning electron microscopy revealed that the dust consists primarily of semi‑spherical and elongated particles, with lead carbonate precipitation occurring preferentially on particle surfaces during leaching. Energy‑dispersive spectroscopy confirmed the conversion of lead sulfate phases to lead carbonate, which progressively limited further selenium and tellurium dissolution. A brief kinetic analysis indicated that selenium dissolution follows a mixed control regime involving surface chemical reaction and diffusion through product layers, whereas tellurium leaching did not exhibit consistent kinetic behavior across the studied conditions. The results demonstrate that sodium carbonate leaching can effectively reduce the mobility of selenium and tellurium while stabilizing lead, supporting its application as a detoxification‑oriented pre‑treatment for lead‑rich metallurgical dusts rather than a conventional high‑recovery extraction process. Furthermore, thermodynamic analysis confirmed the environmental detoxification of the residue through the stable immobilization of lead as cerussite (PbCO3). The macroscopic dissolution behavior was successfully described using an apparent Shrinking Core Model (SCM), revealing the interactive effects of leaching parameters on the kinetic bottlenecks.

Abstract: Resistance spot welding of dissimilar steels is a key Linkage process in the manufacturing of rail passenger car bodies. However, there are problems such as core deviation caused by material physical property differences in the welding of dissimilar steels (stainless steel/low-carbon steel). This study improves the weldability of stainless steel and low-carbon steel by adding a nickel intermediate layer between them. The results show that adding a nickel intermediate layer can Valid compensate for heat Loss, suppress the deviation of the weld nucleus, optimize the size of the weld nucleus, and improve the Stability of the welding quality.

Abstract: Machine learning interatomic potentials (MLIPs) are typically constructed for homogeneous crystalline systems that exhibit only minimal local deviations from equilibrium configurations. However, substitutional alloying elements in multicomponent engineering alloys are often distributed in a locally heterogeneous form. To address this, we develop a fine tuned MLIP based on the MACE foundation model, specifically tailored for Mo based dilute alloys containing one or two out of 20 substitutional elements: Cr, Fe, Mn, Nb, Re, Ta, Ti, V, W, Y, Zr, Al, Zn, Cu, Ag, Au, Hg, Co, Ni, and Hf. The model is trained on more than 7,000 non equilibrium structures derived from first principles density functional theory (DFT) calculations. The optimized large scale fine tuned model attains state of the art accuracy, with mean absolute error (MAE) and root mean square error (RMSE) of 2.27 meV/atom and 3.79 meV/atom for energy predictions, and 13.83 meV/Å and 24.26 meV/Å for force predictions, respectively. Systematic evaluation of model transferability to unseen alloying elements under different data splitting protocols demonstrates that incorporating even a modest set of new element DFT data during refinement reduces the energy MAE below ~20 meV/atom. The fine tuned models reduce the MAE by approximately 7–10 times compared to models trained from scratch, and by 10–20 times relative to zero shot foundation models. This performance gain remains consistent across varying dataset sizes (equilibrium vs. non equilibrium structures) and model scales. Our work illustrates the efficacy of transfer learning from globally homogeneous systems to locally heterogeneous multi element alloy environments, delivering a robust MLIP tool for the accelerated design of multicomponent alloys.

Abstract: This paper investigates the formation mechanism and key influencing factors of freckle defects that arise during the directional solidification of a novel third-generation nickel-based single crystal superalloy turbine blade. A combined experimental and multi-physics numerical simulation approach was adopted. The results reveal that freckle formation primarily results from the coupling effect of solute segregation and thermo-solutal convection during solidification, leading to dendrite fragmentation and subsequent aggregation of equiaxed grains. The resultant density inversion drives upward interdendritic flow, which plays a dual role: it promotes remelting and fragmentation of secondary dendrite arms, while simultaneously opening solute-enriched preferential flow channels that eventually develop into freckle defects. The severity of freckling is closely dependent on both the casting's position within the furnace and its local geometric characteristics. Castings located in regions with poorer heating conditions experience lower temperature gradients and slower solidification rates, significantly increasing their susceptibility to freckle formation. Similarly, on a given casting, the side subjected to less favorable heating is more prone to freckle initiation. This work provides a crucial theoretical foundation for understanding freckle formation in nickel-based single crystal superalloys and offers practical guidance for optimizing blade manufacturing processes, reducing solidification defects, and enhancing blade quality and service performance.

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This study systematically investigates the effects of the final annealing temperature on the microstructural evolution and mechanical properties of an Al-Fe-Si alloy aluminum foil. Scanning electron microscopy (SEM) characterization and tensile tests are employed for analysis. As the annealing temperature is elevated from 240°C to 360°C, the average grain size increases monotonically from 5.2 μm to 9.6 μm. Continuous recrystallization is identified as the predominant grain growth mechanism.Tensile deformation exhibits the homogeneous-plastic behavior without localized necking. The tensile strength decreases significantly in the range of 240–300°C and subsequently undergoes a recovery stage at 300–360°C. The Pronounced elongation anisotropy is observed. The maximum elongation reaches 30–34% along the 45° direction relative to the rolling direction (RD), which is approximately 1.5 times that along the RD (0°).Comparative analysis of the anisotropy indices demonstrates that the aluminum foil annealed at 240°C achieves the minimal tensile strength anisotropy (13.0 MPa) and elongation anisotropy (−4.2%). This indicates optimal comprehensive mechanical performance.These findings provide a theoretical rationale for the industrial optimization of the annealing processes for Al-Fe-Si alloy foils. They are particularly valuable for balancing microstructural regulation and mechanical property enhancement in lithium-ion battery soft-packaging applications.

Abstract: This study systematically investigates the influence of annealing time on the microstructure and mechanical properties of a (CoCrNi)₉₃.₅Al₃Ti₃C₀.₅ medium-entropy alloy. Following hot rolling, the alloy was subjected to annealing treatments at 900°C for 10 min (HA900-10) and 60 min (HA900-60). Microstructural characterization revealed that both alloys contained three types of precipitates: intergranular M₂₃C₆ and MC-type carbides, as well as γ′ phase. The HA900-10 specimen exhibited a low degree of recrystallization, whereas prolonged annealing promoted partial recrystallization, leading to the formation of a slightly heterogeneous structure (HA900-60). Additionally, the extended annealing facilitated the intragranular precipitation of nanoscale γ′ phase. Room-temperature tensile tests demonstrated the HA900-10 and HA900-60 specimens achieving yield strengths of 1276 MPa and 1202 MPa, with total elongations reaching 26% and 28%, respectively. Quantitative strengthening analysis indicated that the strength of HA900-10 primarily originated from dislocation and grain boundary strengthening. For HA900-60, an additional significant contribution arose from the dislocation shearing mechanism induced by the intragranular γ′ precipitates. Analysis of the deformation mechanisms revealed that planar slip, assisted by the formation of stacking faults, dominated the room-temperature deformation, thereby ensuring sustained work-hardening capacity. This research provides a theoretical foundation for tailoring the microstructure and properties of multi-phase medium-entropy alloys through annealing process control.

Abstract: A Ti6Al4V alloy fabrication via laser powder bed fusion (L-PBF) leads to the formation of coarse columnar β grains that give rise to anisotropic mechanical properties and inadequate strength. Incorporating the rare earth oxide, yttrium oxide (Y₂O₃), has proven an effective strategy in enhancing the mechanical performance of Ti6Al4V al-loys. This study systematically investigates the effects of various Y₂O₃ contents on the microstructure and mechanical properties of Ti6Al4V alloys fabricated via L-PBF. The results demonstrate that a Y₂O₃ addition of 0.2 wt.% produces β grains and α phases with average sizes of 61.6 and 7.6 μm, respectively. Transmission electron microscopy observations reveal that Y₂O₃ nanoparticles, together with elemental Y nanoparticles formed by reduction, are distributed both within the α-Ti matrix and along phase boundaries. This distribution effectively reinforces grain boundaries and promotes heterogeneous nucleation, thereby refining the microstructure. Mechanical property tests indicate that the alloy strength significantly improves as the Y₂O₃ content in-creases. Specifically, the alloy with 0.2 wt.%Y₂O₃ exhibits a tensile strength of 1106 MPa, a yield strength of 1074 MPa, and an elongation of 10.0%. This study proposes an in-novative rare earth strengthening method for refining the microstructure of L-PBF-fabricated titanium alloys and comprehensively enhancing their mechanical properties.

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Hydrometallurgical pretreatment of pyrite-bearing concentrates and tailings by hydrothermal interaction with Cu(II) solutions is a promising route for chemical beneficiation and mitigation of acid mine drainage but is limited by passivation caused by elemental sulfur and secondary copper sulfides. Here, the effect of sodium lignosulfonate (SLS) on the hydrothermal reaction between natural pyrite and CuSO₄ in H₂SO₄ media at 180–220 °C was studied at [H₂SO₄]₀ = 10–30 g/dm³, [Cu]₀ = 6–24 g/dm³ and [SLS]₀ = 0–1.0 g/dm³. Process efficiency was evaluated by Fe extraction into solution and Cu precipitation on the solid phase, and products were characterized by XRD and SEM/EDS. SLS markedly intensified pyrite conversion: at 200 °C and 120 min Fe extraction increased from 14 to 26 % and Cu precipitation from 5 to 23 %, while at 220 °C Fe extraction reached 33.4 % and Cu precipitation 26.8 %. XRD confirmed the sequential transformation CuS → Cu_1.8S. SEM/EDS showed that SLS converts localized nucleation of Cu_xS on defect sites into the formation of a fine, loosely packed and well-dispersed copper sulfide phase. The results demonstrate that lignosulfonate surfactants efficiently suppress passivation and enhance mass transfer, providing a basis for intensifying hydrothermal pretreatment of pyrite-bearing industrial materials.

Abstract: Owing to the superior reduction kinetics of limonite and goethite relative to silicates, coupled with the poor beneficiation performance of saprolite-type laterite, the direct carbothermal reduction of saprolite-type laterite exhibits limited nickel selectivity. This study leverages the selective oxidation effect of CO-CO2 atmosphere on metallic iron and its suppression of Fe2+ reduction to promote iron migration from oxides into the silicate phase, achieving homogenization and thereby negating its kinetic advantage in reduction. Parameter optimization experiments revealed that treating pre-reduced minerals with a 30 vol% CO atmosphere at 1200 °C for 20 minutes achieves complete iron homogenization within the silicate phase. Compared with the nickel-iron alloy (containing less than 10 wt% Ni) obtained via RKEF process, the combination of pre-reduction, CO-CO2 treatment, and melting reduction process yielded nickel-iron alloys with nickel contents of 52.1 wt% (FeNi50 alloy) and 64.2 wt% at carbon consumptions of 4.0 wt% and 3.83 wt%, respectively, accompanied by nickel recovery rates of 95.5% and 91.2%. Furthermore, the enrichment of Fe2+ in the slag significantly reduces its melting point to approximately 1450 °C, enabling complete slag-metal separation after smelting at 1550 °C for 10 minutes.

Abstract: The paper focuses on materials characterization and «in vivo» biocompatibility tests of Ti6Al7Nb alloys microdoped by 0.3 wt. % of rareearth elements (REE) to use it as perspective materials to produce personalized medical implants. All Ti6Al7Nb0.3REE alloys (REE Y, Ce, La) were produced by electric arc melting method and characterized by scanning electron microscopy (SEM), optical microscopy (OM), energy-dispersive Xray spectroscopy analysis (EDX), helium pycnometer as well as reducing/oxidation melting methods. The measured true densities increased in the order: Ti−6Al−7Nb−0.3Y (4.4563 ± 0.1075 g/cm³) < Ti−6Al−7Nb−0.3Ce (4.7255 ± 0.2853 g/cm³) < Ti−6Al−7Nb−0.3La (4.8019 ± 0.0111 g/cm³). Diffraction analysis was performed to indicate phases composition and calculate crystallites sizes, crystal orientation and lattice parameters that confirmed REEmicrodoping due to increase of lattice volume. The single-phase Ti6Al7Nb0.3Y alloy had the finest αTi crystallites (22.32 nm), the larger αTi crystallites in the dualphase Ti6Al7Nb0.3Ce and Ti6Al7Nb0.3La (30.77 nm and 29.83 nm, respectively) suggest that the presence of the βTi phase. Hardness (H) and elastic modulus (E) were indicated by nanoindentation and increased in the order: Ti−6Al−7Nb−0.3La (4.01 GPa and 17.7 GPa respectively) < Ti−6Al−7Nb−0.3Y (4.39 GPa and 137 GPa respectively ) < Ti−6Al−7Nb−0.3Ce (4,67 GPa and 146 GPa respectively). In vivo tests showed that Ti6Al7Nb0.3La alloy had statistically significant increase of local inflammation at the one-week mark needed to further research and explanation as well, that could be indicator of toxicity in comparison with other studied alloys.